Investigators continue their probe into a South Dakota train derailment that sent a 55-car Dakota, Minnesota and Eastern freight train slamming into eight rail cars in Brookings. The crash, which investigators say might have occured because of sabotage at a switching station, killed the conductor and injured an engineer early Saturday morning. The Brookings based DM&E is involved in a controversial expansion proposal to send longer, faster frieght trains through Minnesota and South Dakota. Opponents to the expansion say there is no way the two are linked. Minnesota Public Radio's Cara Hetland reports: